Ukraine says there will be no let-up in its punishing long-range drone attacks on Russia until Moscow agrees to peace.
The warning comes ahead of Vladimir Putin meeting Donald Trump in Alaska.
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It was made in a rare interview with one of the key commanders of Ukraine's drone forces.
We met in an undisclosed location in woods outside Kyiv. Brigadier General Yuriy Shchygol is a wanted man.
There is a quiet, understated but steely resolve about this man hunted by Russia. His eyes are piercing and he speaks with precision and determination.
His drone units have done billions of dollars of damage to Russia's economy and their range and potency is increasing exponentially.
"Operations", he said euphemistically, "will develop if Russia refuses a just peace and stays on Ukrainian territory".
"Initially, we had a few drones a month, capable of striking targets 100 to 250 kilometres away. Today, we have drones capable of flying 3,000 to 4,000 kilometres, and that's not the limit, it's constrained only by fuel supply, which can be increased".
His teams had just carried off one of their most complicated and most devastating strikes yet. A massive fire was raging in an oil refinery in Volgograd, or Stalingrad as it was once called.
"If the refinery is completely destroyed, it will be one of the largest operations conducted," Brigadier General Shchygol said. "There have been other major targets too, in Saratov and Akhtubinsk. Those refineries are now either non-operational or functioning at only 5% of capacity."
Oil is potentially Vladimir Putin's Achilles heel. So much of his economy and war effort is dependent on it. Donald Trump could cripple Russia tomorrow if he sanctioned it but so has appeared reluctant to do so, a source of constant frustration for the Ukrainians.
Military activity on both sides has increased as diplomacy has picked up pace.
In another long-range attack, Ukraine says it hit the port of Olya in Russia's Astrakhan region, striking a ship loaded with drone parts and ammunition sent from Iran.
But on the ground, Russian forces have made a surprise advance of more than 15km into Ukrainian territory.
Ukraine says the intrusion can be contained, but it adds to fears about its ability to hold back the Russians along the 1000-mile frontline.
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Russia launches almost nightly drone attacks on Ukraine's cities, killing civilians and striking residential targets.
General Yuriy says Ukraine picks targets that hurt Russia's war effort, and it is constantly honing its capability.
"Each operation", he says, "uses multiple types of drones simultaneously, some fly higher, others lower. That is our technical edge."
How satisfying, I asked, was it to watch so much enemy infrastructure go up in smoke? He answered with detached professionalism.
"It does not bring me pleasure, war can never be a source of enjoyment. Each of us has tasks we could fulfil in peacetime. But this is war; it doesn't bring satisfaction. However, it benefits the state and harms our enemy."
Whatever happens in Alaska, General Yuriy and his teams will continue pioneering drone warfare, hitting Vladimir Putin's economy where it hurts most.
(c) Sky News 2025: Ukraine vows to continue drone attacks until there's a peace deal